Carburetor



A. C. BENNETT.

CARBURETOR.

APPLICATION FILED MAR. 30. 1918.

Patented Sept. '26, 1922.

2 SHEETS-SHEET I.

AQc. BENNETT.

CARBURETOR.

APPLICATION HLED MAR. 30. l9l8.

l A 30 00 1 Patented Sept. 26, 1922 2 SHEETS SHEET 2.

Z11; F/far'neys.

Patents. Set. 26,. 1922.

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1,430,001 NT ism-ca.

OARBURETOR.

Application filed March 30, 1918. Serial No. 225,843.

' p or low. A further object is to provide for heating the air which is supplied to the carburetor when the engine is running atlow speeds, and to deliver a large amount of unheated air to the carburetor when the engine is running at high speeds.

- The full objects and advantages of my invention will appear in connection with the detailed description thereof and are particularly pointed out in the claims.

Referring to the drawings, illustrating the application of my invention in one form,

Fig. 1 is a view in vertical section of my carburetor taken on the irregular line 1-1 of Fig. 2 and showing the valves positioned for low speed. Fig. 2 is a view mostly in vertical section on line 2-'-2 of Fig. 1. Fig 3 is an enlarged detail of a portion of a carburetor, as shown in Fig. .1 but showing the'valves positioned for high speed. Fig. 4 is a view in horizontal section online 4-4 of Fig. 1 showing the valves positioned for slow speed. Fig. 5 is a view similar to' Fig.

'4 but. showing t 0' position of the valves during the operation of changing from low to high speed. Fig.6 is a view similar to Figs. 4 and 5 but showing the valves posi tioned for highspeed.

As illustrated in -the drawings, the exhaust pipe from the engine opens into a chamber 11 formed by a casing 12. Within the chamber 11 is an extended member 13 forming amixin'g chamber 14 of globular shape, mto the upper portion of which depends the lower end ofthe delivery pipe 15 which delivers the carbureted fuel in the usual way from the chamber 14. The lower end of this pipe therefore constitutes an annular member 16 which is spaced from the curved wall of the chamber 14. .The exhaust gases pass around and heat the chamber and escape through a pipe 17 and the member 13 is preferably formed with external ribs OR TO IRENE E. EENNETT,

18 in order to increase the heating surface.

The lower end of the casing is contracted and contains a plug" 19 having helical grooves 20 in its vertical surface which form passageways to give the fuel a whirling motion as it enters the chamber 14. On account of this whirling motion'the heavier particles of fuel willbe thrown into contact with the hot wall of the chamber and vaporized, while the annular member 16 acts as a trap to prevent unvaporized particles escaping into the delivery pipe. Below the plug 19 the casing is curved to form a hori= zontal p1pe member 31having two ports 21 and 22 in its upper side, the port 21 connectlng wlth a chamber 23 and the port 22 connecting with a chamber 24. These two chambers extend around the exhaust pipe 10 and are separated from each other by the partition 25 having the port 26 at its upper portion to afi'ord connection between the two chambers. A by-pass leading from the air Inlet end of the pipe 31 and extending around the exhaust pipe 10 is thus provided. A suitable fuel reservoir 27 has connected with it a passageway 28 formed by a lower wall 29 and an upper wall 30, the latter being spaced from the bottomof the pipe 31 to form a chamber 32 for a purpose which willpresently appear. Two openings33 and 34:, as best shown inFig. 3, extend through the wall 30, the opening 33lbeing controlled by a needle valve 35, the stem 36.7ofwhich extends downwardly through a gland 37 and has its end bent to form an operating'han- 'dle 38. The screw threaded'portion'39 of the stem engages a screw threaded opening in the wall 29 whereby the valve may be adjusted by turning the handle 38 in order to control the fuel supply for low speed. The

opening 33 is fitted with astand pipe 41 whichextends upwardly through an opening 40 in the bottom wall of the pipe 31 and terminates a short distance above the lower-portion of the wall of s'aidjpipe. Rotatabl mounted in openin 40 and concentric with the stand-pipe 41 1s a tubular member 42, the upper end of which is'closed at 4:3 and is provided with a stem {4 to which is secured a throttle lever 45 which ma be operated in the usual manner to partially rotate the member 42. A. butterfly valve 46 is secured to member and this valve has a diameter the same as the diameter of the pipe 31 so that it may be turned to entirely close the passageway in said pipe except for an opening 47 extending into one side of the tubular member and a plurality of perforations 48 extending through the other, or suction side, of the tubular member. Thebutterfly valve has its central vertical portion divided and curved to extend around the tubular member 42 and it is secured thereto in any'desired manner for turning movement with said member, It will be understood that the hole 47 and the perforations 48 extend through the curved portion of the butterfly valve as well as through the tubular member. The opening 34-previously referred to is controlled by a needle valve 49, the stem 50 of which extends downwardly through a gland 51 and has its end bent to form an operating handle 52. A screw threaded portion 53 of the stem engages a screw threaded opening in the wall 29 whereby the valve may be adjusted by turning the handle 52 in order tocontrol the fuel supply for high speeds. The opening 34 is fitted with a standpipe 58 which extends upwardly through an opening 54 in the bottom of the. wal of the pipe 31 and terminates a short distance below the upper portion of the wall of said pipe. ltotatably mounted in the opening 34 and concentric with the standpipe 58 is a tubular member 55, the upper end of which is closed and rotatably mounted in a socket 56 provided in the upper portion of the wall of the pipe 31. The butterfly valve 57 is securedto the member 55 and this valve has a diameter the same as the diameter of the pipe 31 so that it may be turned to normally'close the passageway in said pipe. When said valve is closed it is obvious that communication can be had from the inlet end of the pipe through the carburetor only through the bypass constituted by the ports 21 and 22, the chambers 23 and 24 and the port 26. The butterfly valve 57 is secured to the tubular member 55 in the same manner that the butterfiy valve 46 is secured to the tubular member 42, and in the wall of the tubular member 55 are a plurality of perforations 59 located in the suction wall.

As previously stated, the butterfly valve 46 and the tubular member 42 to which it is secured may be partially rotated by throttle lever 45. In order to also 0 crate the tubular member 55 and the valve 5 car ried thereby, I provide in the chamber 32 a connection between the two tubular members. This connection comprises a bar 60; one end of which is pivoted at 61 to an arm 62 which has a portion 63 extended around the tubular member 55 for securing it thereto. The curved end of the bar 60 is provided with a slot 64 which is concentric with the axis of the tubular member 42. la. this atmospheric Leeopoa slot is a pin'65 on the end of an arm 66 which has a portion 67 extending around the tubular member 42 for securing it thereto. Secured'to the bar 60 is a leaf spring 68 which engages the wall of the chamber 32 and which when compressed, as shown in Fig. 6, tends to return the bar 60 to the position shown in Figs. 4 and 5.

The operation and advantages of my invention will be apparent from the foregoing description. In the .low speed position. shown in Fig. 4 both butterfly valves are closed and the air is drawn through the bypass around the exhaust pipe which preheats it. The heated air passes through the opening 47 in the tubular member 42 and directly over the upper end of the standpipe 41. Fuel will be drawn up said standpipe into-the current of air and the mixture will pass out through the perforations 48 toward the mixing chamber 14-. The mixing and vaporizing are completed in said chamber and thus a thoroughly vaporized homogeneous mixture suitable for lowspeeds is supplied to the engine. However, in order to insure perfect carbureting for high speeds it is desirable to supply an amount of oxygen proportionally greater than is supplied at low speeds since the travel of the incoming air at high speeds is much greater and a greater amount of fuel is drawn into the air which would tend to increase the richness of the mixture. Therefore, 1 supply air at temperature only at high speeds, this air being of greater density than the heated air and hence containing more oxygen per unit volume than is contained by the heated air. This result is obtained by operating the butterfly valves in the manner previously indicated. Upon operating the throttle lever the valve 46 is first opened and the supply of heated air is increased. This causes fuel to rise in the standpipe 58. Upon continuing to turn the throttle lever the valve 57 is opened and a large amount of air at atmospheric temperature is drawn through the inlet tube. Fuel is drawn through the erforations 59 and mixes with this air. With this construction, in addition to completely vaporizing gasoline, it is possible to satisfactorily vaporize heavy oils, such as kerosene, it being understood for heavy oils it is desirable to deflect more heat around the chamber 14. When the engine is running at low speed, the carbureting effect of the expanded chamber is increased by preheating the air. When, however, the engine is running at high speed and it is desirable to carry as large an amount of mixture through the carburetor as possible the opening of the valve 57 causes the by-pass to be put out of commission and the air passes directly through the air tube to the chamber 14. By taking all of the air regardless of the speed of the engine through means for tated.

I claim 1. A carburetor comprising a mixing chamber, means for supplying fuel to said mixing chamber, an air inlet tube leading to said chamber, a casing forming a by-pass for said tube around the exhaust pipe of the engine, a valve in said inlet tube for deflectin the incoming air through said bypass, a valve controlling the passage through said mixing chamber, means for first opening said last mentioned valve to increase the supply of heated air, and means for then opening said first mentioned valve to permit un heated air to pass directly through said in: let tube.

filtering the air is greatly facili- 2. A carburetor comprising a mixin chamber, means for supplying fuel to said mixing chamber, an air inlet tube leading to said chamber, a casing forming a bypass for said inlet tube around the exhaust pipe of the engine, a valve in said inlet tube 'for deflecting the incoming air through said bypass, a valvefor controlling the passage through said mixing chamber, a throttle lever connected to said last mentioned valve 0 for operating the same, an operating member connected with said first mentioned valve, and a lost motion device connecting said operating member and said ast mentioned valve.

In testimony signature ASHLEY C. BENNETT.

whereof I hereunto aflix my 

